Niels

I have this hooked up to an Arduino Uno board, and can set and read time with no problems, although things only work in SPI mode 3.

Next I tried to get the SQW pin to trigger an interrupt on the Arduino every second, and that’s where I’m not getting things to work. Hoping someone can help me.

I hooked up Arduino pin 2 to SQW, and added a 4.7K resistor from SQW to Vcc. In my sketch, I do pinMode(2,INPUT) and then hook up the interrupt function. I then set register 0x8E to 0x60. I was expecting the interrupt to fire once a second, but it never does.

If I disconnect the connection to SQW and move by hand touch it to GND, the interrupt fires as I would expect.

I unfortunately do not have a scope or logic analyzer handy… I’d appreciate any insight on what I’m missing here.

As a SparkFun customer, I primarily care about your product selection, your excellent website, and your great customer service. You have what I need to get done what I need to get done, you ship what I need, when I need it, and the orders are always right. When I call, there’s someone to answer the phone. I care that you stock the right stuff at a fair price.
SparkFun keeps on getting my business because they meet my needs and provide a good shopping experience, in other words, what is being done, works. If that takes skateboards, dogs, beer, and a great company culture… awesome. Keep on doing what it takes. Congrats on figuring out what your corporate identity is, both towards your customers, and for your people. You need the two to work hand in hand to have a successful company, and it looks to me like you’ve hit on a formula that works.
Growing a company from an idea to 100+ people, and making it profitable, is a hard thing to do. Over the last 2 decades I’ve done it twice, once as a founder, and once as a very early employee. People, in both cases, are the key asset that made it work. As SparkFun is doing, you do what it takes to keep them happy, because happy people are loyal people. That goes for the staff that works there, the companies they do business with, and the people that buy from them.
So congrats on the success, keep doing what you’re doing, and I hope you manage to maintain your corporate culture and remain successful.

Real easy to use, works flawlessly! Soldering on the MIDI connectors is a snap. As noted, headers are not included, need to order those separately. The board includes some extra LEDs (the blinking lights in my application surprised me.. :) ). There’s 2 pots and 3 push buttons which are all optional, works fine without those soldered in.
One note: You might want to disconnect the MIDI cable when programming the device, it looks like there’s some bytes sent out to the MIDI OUT (even with the little switch set in PROG) that arrive at connected MIDI gear. My patch bay gets in a weird state whenever I upload a new sketch.
(Not related to the product, but The MIDI example in the Arduino software (0021) has a space missing in the for statement in line 32, after int there should be a space.)

Just got one of these ‘working’ with an Arduino board today, just bought from SparkFun last week. Here’s what I found:
1. They’re not kidding about the voltage requirement being 6 or 7 VDC, Running this on 5V seems to result in significant backlight and contrast variations.
2. The box function claims to take 5 parameters, two x/y coordinates and a byte to indicate black or clear pixels according to the datasheet; however in reality the function only takes 4 parameters; the fifth one is sent to the screen as text output. (Verified in driver source code)
3. Although the line function does take 5 parameters (2 pairs of x/y and a set or clear byte), it appears to not correctly interpret the clear command; I seem to be unable to ‘clear’ a line of pixels using the line command
4. It turned out to be very easy to overrun the controller with data; liberal application of delay() was required to keep everything moving
Needing just 1 output pin to address the display is a major plus, dealing with the firmware issues on the backpack is a pain.
Niels.

SparkFun is an online retail store that sells the bits and pieces to
make your electronics projects possible. Whether it's a robot that can
cook your breakfast or a GPS cat tracking device, our products and
resources are designed to make the world of electronics more accessible.

In addition to products, SparkFun also offers
classes and online tutorials to help educate
individuals in the wonderful world of embedded electronics.